LiBF4 is used as an electrolyte in Lithium-ion batteries. Using LiBF4 instead of the more common LiPF6 salt is advantageous in some applications due to its relative tolerance of temperature extremes and moisture. For example LiBF4 can tolerate a moisture content up to 620 ppm at room temperature whereas LiPF6 readily hydrolyzes into toxic POF3 and HF gases, often destroying the battery's electrode materials. Disadvantages of the electrolyte include a relatively low conductivity and difficulties forming a stable solid electrolyte interface with graphite electrodes.
Because LiBF4 and other alkali-metal salts thermally decompose to evolve boron trifluoride, the salt is commonly used as a convenient source of the chemical at the laboratory scale: